Effect of melatonin on developmental rate of LPS treated early mouse embryos. (A) The time schedule of the treatment designs of LPS and melatonin. (B) In vitro cultured mouse embryos of blastocyst stage were observed by inverted fluorescence microscopy (EVOS® FL, AMG) (Scale bar = 200 µm). (C) A graph of each development stage. The numbers of embryos tested in each group are at least 20 and experiments were performed repeatedly at least three times. Data are expressed as mean ± standard error mean (SEM) expressed in one-way ANOVA. A significant difference between treatments indicates as p-value; **p < 0.01. LPS, in vitro culture medium with 12.5 µg/mL LPS; MT1, melatonin 1 µM/mL; MT10, melatonin 10 µM/mL. (D) In vitro developmental rates of mouse embryos cultured with LPS and melatonin. LPS, in vitro culture medium with 12.5 µg/mL LPS; MT 1, melatonin 1 µM/mL; MT 10, melatonin 10 µM/mL.